Dust-cap for valves.



A. C. SAVIDGE.

' DUST CAP FOR VALVES.

APPLICATION FILED MAY 22. 1916.

Patented J an. 2, 1917.

WITNESS enlarged section and Fig. 3 is an enlarged sectlon on the hne outside edges of the screw threads on the: *valve stem, so that it" canslide along the thereon,

5 of the sleeve 19 whichis toward the o en,

'useful Dust-Cap for Valves,

ALBERT C. SAVIDGE, OF INDIANAPOLIS, INDIANA.

DUST-CA1 FOR VALVES.

Specification bf Letters Patent.

Patented Jan: 2, 1917.

Application filed May 22,1916. Serial No. 99,140.

To all whom it may concern:

Be it known that I, ALBERT G. Savmon, a citizen 4 of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a new and of which the following is a specification. v I

It is the object of my invention to provide for the valve of a pneumatic tire a dust cap which is easily attached and removed without requiring to be screwed the whole length of a valve stem, which when in place may be firmly seated against its abutment, and which requires no axial pressure for effecting attachment or removal.

The accompanying drawing illustrates my invention.

Figure 1 isacentral-axial section through a dust cap embodying my invention, showing it in place on a valve stem; Fig. 2 is an on the line 2-2 of Fig; 1;

3-3 of Fig. 1.

The valve stem 10 is of the practically universal type, being provided with the usual nut 11 for clamping it in place-on its associated wheel rim 12, through which it extends to the tire, b ing threaded throughout its length, and being provided with two opposite flat faces 13 for receiving a suitable wrench. I take advantage of these flat faces 13 for accomplishing the purpose of this invention.

My improved dust cap has an outer sheet metal shell 15, which is closed'at one end in the usual manner and open at the other to receive the valve stem .10, being sufliciently long to receive the whole valve stem within it. This shell is enlarged for a portion, of its length near its open end, but thisenlarged portion 16 does notextend quite to the open end of the shell, Fixed in one end of this enlarged portion 16 is 'is threaded internally,

an annulus 17 which and which is conveniently held against any movement in the shell 16 by'a prick'punch mark 18. Threaded within the annulus 17 is an externally threaded sleeve 19, which is shaped inter- V loosely against the flat nally to fit fairly faces 13 of the valve stem and to clear the valve stem but is prevented from turn ng as clear from Fig. 2. Near that end end-of the Y shell .is'asplit 20, shown as havingrfour parts (Fig. 3), which split nut is surrounded by a tightening spring 21 which tends to crowd the parts of the split I nut together so that the threads on its interior engage with the threads on the valve stem 10. The two axial ends of this split nut are -inwardly tapered, so as to form frusto-conical surfaces 22, which cooperatewith similar surfaces on the adjacent axial endsof members 24 and 25, which are sufficiently large interiorly to clear the outer edges of the threads of the valve stem 10 The member '24 is interposed between the split nut 2(1 andthe sleeve 19, and is shown as a separate member from such sleeve, though this separateness is not essential, the two' parts 19 and 24 bearing against each other on cooperating plane faces. The member 25 is located in that end of the enlarged portion 16 which is toward the open end of the shell 15, and is held in place .by the crimping in'of such open end, as clear from Fig. 1.

By turning the shell 15, the annulus 17 is turned with it; but on account of the flat faces 13 of the valve stem the sleeve 19 is prevented from turning when the dust cap is in' place on the valve stem. In consequence. there relative turning between the annulus 1'7 and the sleeve 19, and the engaging screw threads of such parts cause such relative turning to produce relative axial motion also. This relative axial motion canseslthe sleeve 19 to travel lengthwise in the enlarged portion 16 of the shell 15. When such travel is toward theopen end of the shell (or downward in .Fig. 1), it forces the members 24 and 25 together-so that the cooperation of the frusto-conical faces on such members and on the split nut 20 spreads the parts of the split nut apart against the actlon of the spring 21 so as to clear the threads on the valve stem and permit the removal "or attachment of the dust cap. When such travel is toward the closed end of the shell (or upward in 'Fig. 1) it permits the members 24 and 25'to separate sothat the spring 21 may force'inwa-rd the parts of the split nut so as to cause the threads on such split nut to engage the threads on the valvestem and thus lock the dust cap in vplace .on'the valve stem. This locking can take place with the dust cap in any place alongthe valve stem, for-it is not'essential that there :be any axialthrust on the dust cap as to produce ia reaction against the which produces the locking jclamping nut 11; but preferably the locking is done when the open end of the shell 15 is by the'turning against the nut 11, so that the dustcap is carried axially more firmly into engagement with the nut 11 so as to form a dust-tight J pint. v Y

fI'claim as my invention:

1;: A dust cap for valvestems, comprising d-an outer shell provided with an internally threaded part movable therewith, an externallythr'eaded sleeve threaded in said inter- 'nally threaded part and shapedinternally so that it is movable axially on the valve stem but is -prevented from turning-on the valve I stem,-and a split nut the partsof which are spring-pressed inwardly into cooperative-relation withth'e threads on the valve stem but "are movable outwardly out of such cooperainternally an exterbut is-prevented from turning-on the valve stem, and a split. nut the parts of which are spring-pressed radiallyin one direction but I are movableradially in the other direction bythe axial movement of said sleeve. relative to said shell. '3." A dust cap for valve stems, comprising an outer shell, a sleeve shaped internally so that it is movable longitudinally of -the valve stem but is prevented from turn- .ing thereon, said sleeve and said shell hav- I I mg a screw thread connection, and a split nut the parts of which are spring-pressed inwardly into cooperative relation with the threads on the valve stem but are movable outwardly out of said cooperative relation by the axialmovement of said sleeve rela- 45 tive to said shell.

4. A dust cap for valve stems, comprising an outer shell, a sleeve shaped. internally 7 'so that it is movablelongitudinally of the valve stem but is prevented from turning thereon, said sleeve' and said shell having a screw-thread, connection, and a split nut the parts of which are spring-pressed radially in one direction but are movable radially '.-.in the other direction by the axial movement of said sleeve relative to saidshelll 5. A dust cap for valve stems, comprising an outer shell, a sleeve shaped internally so 'that it. is movable longitudinally of the I, valve stem but is prevented from turning thereon, said sleeve and said'shellhaving a screw thread connection, and a spllt nut the :partSbf which are spring-pressed inwardly into cooperative relation with the threads on' 'the valve stem, said split nut having an mwardly tapered face at an axial end and comprising.

clearing such threadsf t 7. A dust cap for valve stems, comprising i an outer shell, a sleeve shaped internally so said shell having an abutment between which and said sleeve said split nut is located, so that by turning said shell in one direction the resultant axial relative movement of said sleeve and abutment produces a cam action on saidinwardly tapered face of a split nut between them to force the parts of said split nut out ofcooperative relation with the threads on said valve stem,

6, A dust cap for valve stems, comprising an outer shell, a sleeve shaped internallyso that .it is movable longitudinally of the valve. stem but is prevented from turning thereon, said sleeve and said shellhaving' .,a screw thread connectlon, and; a- 'spllt -nut the parts of which are sprlng-pressed radially in one direction, said split nut having a tapered face at an axial end and said shell having an abutment between which and said sleeve said split. nut is. located, 'so

that by turning said shell in one direction the resultant axial relative movement of said sleeve and abutment produces a cam action on said tapered face of the split nut between them to force the parts of said split.

nut radially inj'the other direction against their spring, said split nut parts whenmoved radially in'one direction cooperating with the threads on the valve stem and when moved;radiallyiin 'theother dire'ctitjn 9 that it is movable longitudinally of the valve stem but is prevented from turning thereon, said sleeve and said shell having a 'screw'thread' connection, and'a' split nut the parts of which are spring-pressed-im' wardly intocooperative relation with the threads on the valvestem, said'split nut having an inwardly tapered face at each 'axialend'and' said shell having an abut-g ment between which andusaid sleeve said split nut is located, so that by turning said shell in one direction the resultant axial relative movement of said 'sleeve and abutment produces opposing cam aCtlOIlSOIl said inwardlytapered end faces of the split nut between them to force the'pa-rts of said split nut out of cooperative relation with the' threads on said valve stem.

8. A dustcap for valve stems, comprlslng an outer shell, a sleeve shaped internally so that it is movable longitudinally of the valve stem 'but is prevented from turning;

thereon, said sleeve and saidshell havinga screw thread connection, and a split nut'the parts of which are spring-pressed radially in one direction, said split nut having a tapered face at each axial end .a-nd said shell having an abutment between which and said" sleeve said split nut is located, so that by turning said shell in one direction the resultant relative axial movement of said sleeve and abutment produces opposing cam actions on said tapered end faces of the split nut between them to force the parts of said split nut radially in the other direction against their spring, said split nut parts when moved radially in one direction co. operating with the threads on the valve stem and when moved radially in theother direction clearing such threads. r

9. A dust cap for valve stems, comprising an outer shell, a sleeve mounted within said shell and shaped. internally so that it is movable axially on the valve stem but is prevented from turning thereon, said sleeve and shell being interconnected so that when turned relatively to each other relative axial movement is also produced, and a split nut the parts of which are radially movable relatively to each other, said split nut and said sleeve being interconnected so that upon relative axial movement of said sleeve and shell .radial movement of the parts of the split nut is produced.

10. A dust cap for valve stems, comprising an outer shell, a sleeve mounted within said shell and shaped internally so that it is movable axially on the valve stem but is prevented from turning thereon, and a split nut the parts of which are radially movable relatively connected with said shell and said sleeve so that upon relative turning of said shell and sleeve radial movement of theparts of the split nut is produced.

In witness whereof, I- have hereunto set my hand at Indianapolis, Indiana, this 13th day of May, A, D. one thousand nine hundred and sixteen.

ALBERT C. SAVIDGE.

to each other, said split nut being 

